Some times a sysadmin faces situations where his/her knowledge is far away from what's needed. Or maybe he/she may need to get into a topic suddenly because of a new application, new requirement, and so on.

One may go the classical way of seeking for a book, googleing around and getting disperse info. I prefer to go another way: getting subscriptions to services that may provide information fast and on the go.

In my case, I'm a member of SAGE, a group of system administrators sponsored by SAGE, the subscription is $45 / year and you get access to a mailing list where you can ask and give help on different sysadmin topics, and also you get access to "mini books" covering topocs like: oracle administration, centralized system administration, and so on. If you want more info, have a look at: http://www.usenix.org/membership/classes.html#sage

I'm also paying a monthly subscription to Safari, an online bookshelf from O'Reilly, where you can get online versions of O'Reilly books, and also online versions of books from other vendors. By $22/month you get a bookshelf with ten slots (most books use 1 slot only) and 5 pdf generation token, so you can rende up to 5 chapters monthly. I've been using the service for 4 months now and still haven't used all the tokens (they are cumulative, if you don't spend them in one month, you keep them for the next one.)

Taking in account the cost of the printed books ($30-$60), the transportation to Barcelona (add another $15) and depending on availability, I'm really happy of having the chance of getting instant access to all this media, and being able to get PDF renders at a reasonable price.